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• First Life cycle assessment analysis for citrus residue management in China. • The impacts of conventional treatment and valorisation systems were compared. • Valorisation systems had greater potential to improve environmental impacts. • Better energy efficiency and renewable energy can significantly reduce impacts. This study conducted the first life cycle analysis for citrus residue (CR) management systems in China. The results indicated conventional waste treatment systems were not suitable for CR management in China. Although feed system seems to be a favourable option, the uncertainty analysis suggested valorisation system could achieved better performance in global warming, eutrophication and human toxicity. The environmental impacts of valorisation systems were more sensitive to energy consumption. For silage and single cell protein (SCP) system, the environmental impacts could be significantly reduced by improving the energy use efficiency or using more renewable energy. In comparison, although the environmental impacts of biorefinery system were less favourable than SCP and silage systems. The multiple extraction unit had less impact than reported values in other studies. Further research in biorefinery system can focus on increasing the energy efficiency of pre-treatment or reuse of extraction chemicals. [ABSTRACT FROM AUTHOR]

We theoretically investigate the correlated electron dynamics in strong-field nonsequential double ionization (NSDI) of Ar by the parallel two-color pulses consisting of 800- and 400-nm laser fields with the semiclassical ensemble model. Our calculations show that the momentum distributions of Ar 2+ in the direction parallel to the polarization of laser field exhibit the single- or double-hump structure, depending on the relative phase of the two-color fields. Back analysis of the NSDI trajectories reveals that recollision of returning electron is well confined in a time window of several attoseconds, and the position of which can be controlled with attosecond precision by changing the relative phase of the two-color fields. Thus, the recollision energy is accurately controlled with the two-color fields. As a consequence, the time delay between the double ionization and recollision changes with the relative phase, resulting in the relative-phase-dependent ion momentum distributions. More interestingly, the different peaks of ion momentum spectra result from the NSDI events with different time delays between double ionization and recollision. Thus, the corresponding correlated electron dynamics for different peaks in the ion momentum distributions can be directly determined in the two-color fields. [ABSTRACT FROM AUTHOR]

The present work is focused on the fluidization behavior of different mixed binary nanoparticles (Fe 2 O 3 + SiO 2 , Fe 2 O 3 + TiO 2 , and Fe 2 O 3 + ZnO) under the influence of a vibrated field. The results reveal that the iron-containing nanoparticle mixtures with different mass fractions can achieve uniform fluidization in the initial bed height of 40 mm, amplitude of 3.0 mm, vibration frequency of 40 Hz, and binary mixtures containing nano-SiO 2 and nano-Fe 2 O 3 have commendable fluidization behavior. Richardson–Zaki equation index indicates that the particulate dispersion degree of the different proportion mixtures increases as the mass fraction of APF (agglomerate particulate fluidization) nanoparticle increases. For a binary nanoparticle mixture containing different proportions of high content nano-SiO 2 and nano-Fe 2 O 3 , n /4.65 is closer to 1 and the relative deviation is smaller than that containing a high content TiO 2 and ZnO, indicating that the system has a good dispersibility. [ABSTRACT FROM AUTHOR]

Abstract: Using three-dimensional classical ensembles, we have investigated the enhancement of double ionization of perpendicularly aligned H 2 molecules by a 800nm laser pulse with intensity ranging from 1×1014 W/cm2 to 6×1014 W/cm2. The simulated results show that double ionization probability of H 2 strongly depends on R and reaches a maximum at an intensity independent critical distance R C ≈5a.u. Furthermore, the enhancement of double ionization is more pronounced in the cases of weaker or stronger fields. These results, a well indication of the influence of molecular structures and laser–molecule interactions on double ionization of diatomic molecules, are analyzed in detail and qualitatively explained based on the field-induced barrier suppression model and back analysis. [Copyright &y& Elsevier]

• Degradation characteristics of 4 organics in pharmaceutical wastewater was studied • SCPW exhibited good biodegradability when H 2 O 2 dosage reached 0.6 Q • The biodegradability of SCPW was improved due to oxidation intermediate of organics • The removal of organics and COD was in line with the second-order kinetic model • The greater the E RB3LYP of the organic, the more difficult it was to be removed Present study deals with the treatment of simulated chemical pharmaceutical wastewater (SCPW) using Fenton oxidation process for the degradation of typical pollutants containing n-butanol, ethyl p-nitrobenzoate, 4, 7-dichloroquinoline and ethyl acetoacetate. The effects of operational parameters like the initial pH, H 2 O 2 /Fe2+ molar ratio, H 2 O 2 dosage and reaction time on the degradation efficiency of pollutants and biodegradability of SCPW were investigated. The Fenton reaction steps and the removal kinetics of SCPW were analyzed. Finally, the effects of the molecular structure on the degradation efficiency of organics were investigated. The degradation ratio of n-butanol, ethyl acetoacetate, 4, 7-dichloroquinoline, ethyl p-nitrobenzoate and chemical oxygen demand (COD) in SCPW is 56%, 75%, 100%, 78% and 38%, respectively, for conditions of initial pH of 2.5, H 2 O 2 /Fe2+ molar ratio of 20, H 2 O 2 dosage of 0.6 Q (Q is the theoretical dosage of Fenton reagent) and reaction time of 30 min. The reaction steps analysis indicated that the biodegradability of SCPW was improved mainly by the oxidation intermediate of pollutants. The kinetics study showed that the removal processes of pollutants and COD were consistent with the second-order kinetic model. Quantum chemical analysis showed that the correlation between the total energy E RB3LYP and removal kinetic constant K [RH] was most significant, and E RB3LYP was negatively correlated with K [RH]. The results indicated that the higher the total energy of the organics, the more difficult it was to be removed. The findings reported herein are significant to predict the treatment efficiency of pollutants in real pharmaceutical wastewater. [ABSTRACT FROM AUTHOR]